While testing my changes, I found a bug in test_sys:
./python -X tracemalloc -m test test_sys -v -m test_getallocatedblocks
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ERROR: test_getallocatedblocks (test.test_sys.SysModuleTest)
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Traceback (most recent call last):
File "/home/vstinner/prog/python/master/Lib/test/test_sys.py", line 770, in test_getallocatedblocks
alloc_name = _testcapi.pymem_getallocatorsname()
RuntimeError: cannot get allocators name
Attached PR 12797 fix it.